The achievement of the display technology is to rebuild a visual sensation to the world for human eyes. Nowadays, the display technologies mainly include the Liquid Crystal Display (LCD) and the Organic Light-Emitting Diode (OLED). The development of OLED is later than the development of LCD, and OLED has a higher cost and restricted life-time. However, the dark state of LED is not good enough, so that the contrast ratio of LCD is worse that the contrast ratio of OLED due to the self-emissive characteristic of OLED. To overcome the disadvantages of LCD, dynamical backlight adjustment for divided frame is often used. To implement the dynamical backlight adjustment, relevant hardware and dynamical control algorithm are essential. Good algorithms can make the backlight control match with images possible.
For the dynamical backlight adjustment for whole frame or divided frame, the backlight control is relevant to the statistic of the gray scale of one block or one frame. Usually, the backlight brightness of one block or one frame is determined by the maximum gray scale, the average gray scale or other reference gray scales. Thus, ideally, the backlight brightness varies with time. When there are noises, the backlight brightness will vary too frequently such that flickers seen by human eyes occur.